Reverse joint replacement device and methods thereof

ABSTRACT

Embodiments relate to a joint replacement device, including a fixed socket including an inner surface and an outer surface supporting a ball, an articulating socket including an inner surface and an outer surface the inner surface in contact with the ball and a stem component attached to the outer surface of the articulating socket. The inner surface of the articulating socket articulates with the ball and the outer surface of the articulating socket can articulate with the inner surface of the fixed socket.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 13/448,906, filed on 17 Apr. 2012, which claims the benefit under 35USC §119(e) to U.S. Provisional Patent Application No. 61/477,710 filedon 21 Apr. 2011, and which applications are incorporated herein byreference. A claim of priority to all is made.

BACKGROUND

Traditionally, the socket portion of a standard total hip replacementconsists of a metal hemispheric socket with a porous outer surface tofacilitate bone growth into the socket. The socket also includes a lineron the inner surface for articulation with the ball. The femoral side ofa hip replacement usually includes a ball supported by a stem componentforced into the center, hollow portion of the bone of a patient. Thestem is fastened to the femur with either cement or by bone growth intoa porous outer surface of the stem. The ball, positioned on the end ofthe stem, articulates with the liner of the socket and is attached tothe stem via a cold weld and trunnion.

A common problem in hip replacements is dislocation. In dislocation, theball (which is held in the socket by soft tissue around the hip) comesout of the socket causing great pain and the inability to use the hip orwalk. The ball must be manipulated back into the socket with sedation oreven general anesthesia. The sedation or anesthetic carries risk, asdoes the manipulation of the hip-components can break or come looseduring the manipulation. Once a hip has dislocated, it is more likely tore-dislocate and may happen enough to require repeat surgery. Revisionsurgery for hip dislocation is often unsuccessful or not worth the risksto the patient.

The most common method of hip dislocation is for the ball to fall out ofthe bottom of the socket when the hip is flexed, adducted or internallyrotated. This dislocation occurs because the ball moves beyond thecoverage of the socket with this maneuver and thus slips out of place.Once out of place, it usually stays there and is accompanied bysignificant spasms and pain.

SUMMARY

Embodiments relate to a joint replacement device, including a fixedsocket including an inner surface and an outer surface supporting aball, an articulating socket including an inner surface and an outersurface the inner surface in contact with the ball and a stem componentattached to the outer surface of the articulating socket. The innersurface of the articulating socket articulates with the ball and theouter surface of the articulating socket can articulate with the innersurface of the fixed socket.

Embodiments also relate to a reverse joint replacement socket includinga substantially hemispherical socket and a ball attached to an innersurface of the socket. The socket can attach to an acetabulum or glenoidfossa. Additionally, embodiments describe a reverse joint replacementdevice including an articulating socket including an inner surface andan outer surface the inner surface in contact with a ball and a stemcomponent, attached to the outer surface of the articulating socket. Theinner surface of the articulating socket articulates with the ball andthe outer surface of the articulating socket can articulate with aninner surface of a fixed socket.

Embodiments also relate to methods thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate non-limiting example embodiments ofthe invention.

FIG. 1 is a perspective view of a reverse joint replacement device,according to some embodiments.

FIG. 2 is a prospective view of a reverse joint replacement device,according to some embodiments.

FIG. 3 is a front view of a fixed socket, according to some embodiments.

FIG. 4 is a front view of an articulating socket, according to someembodiments.

FIG. 5 is a side view of an articulating socket with liner, according tosome embodiments.

FIG. 6 is a front view of an articulating socket without liner,according to some embodiments.

FIG. 7 is a perspective view of a fixed socket with ball, according tosome embodiments.

FIG. 8 is a perspective view of a ball and post, according to someembodiments.

FIG. 9 is a perspective view of a ball and post with base, according tosome embodiments.

FIG. 10 is a perspective view of a ball and post with base, according tosome embodiments.

FIG. 11 is a cross-sectional view of a fixed socket with ball, accordingto some embodiments.

FIG. 12 is a cross-sectional view of a reverse joint replacement device,according to some embodiments.

FIG. 13 is a block flow diagram of a method of using a joint replacementdevice, according to some embodiments.

FIG. 14 is a block flow diagram of a method of making a jointreplacement device, according to some embodiments.

DETAILED DESCRIPTION

Throughout the following description, specific details are set forth inorder to provide a more thorough understanding of the invention.However, the invention may be practiced without these particulars. Inother instances, well known elements have not been shown or described indetail in order to avoid unnecessarily obscuring the invention. Thedrawings show, by way of illustration, specific embodiments in which theinvention may be practiced. These embodiments may be combined, otherelements may be utilized or structural or logical changes may be madewithout departing from the scope of the invention. Accordingly, thespecification and drawings are to be regarded in an illustrative, ratherthan a restrictive, sense.

All publications, patents and patent documents referred to in thisdocument are incorporated by reference herein in their entirety, asthough individually incorporated by reference. In the event ofinconsistent usages between this document and those documents soincorporated by reference, the usage in the incorporated referencesshould be considered supplementary to that of this document; forirreconcilable inconsistencies, the usage in this document controls.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more”. In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A, B or C” includes “A only”, “B only”, “C only”, “A and B”, “B and C”,“A and C”, and “A, B and C”, unless otherwise indicated. The terms“above” and “below” are used to describe two different directions inrelation to the center of a composite and the terms “upper” and “lower”may be used to describe two different surfaces of a composite. In theappended aspects or claims, the terms “first”, “second” and “third”,etc. are used merely as labels, and are not intended to impose numericalrequirements on their objects.

Embodiments of the present invention describe a reverse jointreplacement device and methods thereof. Although described often asuseable in a hip replacement surgery, the device may also be used forshoulder replacement surgeries. In the reverse joint replacement device,the fixed socket is still placed in the patient's own socket oracetebulum (or glenoid fossa for shoulder surgeries), but a liner is notrequired, in the traditional manner, on the inner surface of thissocket. Instead, a ball is attached to the inner surface of the fixedsocket. An articulating socket is then attached to the stem componentand articulates with the ball.

With the ball and socket reversed, the hip becomes more stable as itundergoes flexing, adducting or internal rotation. Dislocation is nowmuch less likely to occur, if not completely prevented. If the devicestarts to dislocate, it will be stopped by the fixed socket. The fixedsocket may be lined on its periphery to articulate with the outersurface of the articulating socket, if the articulating socketdislocates from the ball. This mechanism provides an additional layer ofprevention from dislocation. The articulating socket articulates withthe ball in a more stable fashion and the outer surface of the socketcan itself articulate with the inner surface of the fixed socket, ifnecessary to prevent dislocation.

This reverse joint replacement device and method may be utilized in aprimary surgery or in a revision surgery. Frequently, in revisionsurgery, the socket must be removed which increases the magnitude of thesurgery tremendously. This is not desirable, as the most commondislocation patients are elderly women who often suffer complicationsfrom major surgeries. In a revision surgery, the ball may be attached tothe existing fixed socket, such as by utilizing the insertion toolfitting of the fixed socket used to originally place the socket in theprimary surgery. The articulating socket can then replace the existingball on the stem component, without removing it from the patient's bone.Revising the articulating surfaces requires significantly less surgerythan revising whole implants at their bone or metal interfaces-whethercemented or bone ingrown porous.

Referring to FIG. 1, a perspective view 100 of a reverse jointreplacement device is shown, according to some embodiments. A stemcomponent 106 is in contact with an articulating socket 102. The stemcomponent 106 and articulating socket 102 may be one-piece constructionor be in contact via a fitting. An example of a fitting includes maletrunnion 108 and female trunnion 110. The articulating socket 102 mayoptionally include a liner or lining 112.

A fixed socket 104 supports a ball 114 on the inner surface 120 of thefixed socket 104. The ball 114 may be one-piece construction with thesocket 104 or attached via a post 118 with base 116, for example. Thearticulating socket 102 contacts and articulates with the ball 114 (seeview 200 of FIG. 2).

The articulating socket 102 may include an optional liner or lining 112that substantially covers the front and inner surfaces of thearticulating socket 102 (see front view 400 of FIG. 4). The lining 112may be polyethylene or a metal or ceramic liner, for example. The lining112 may be removeably attached to the articulating socket 102 orpermanently or semi-permanently attached, for example. The lining 112may be removable by utilizing a compression fit, locking tabs, frictionor other mechanisms. The lining 112 may be permanently orsemi-permanently attached by utilizing an adhesive or other bondingmechanism.

The articulating socket 102 may be substantially hemispheric and may bemanufactured of a durable material, suitable for invasive medicalinsertion, such as titanium, metal alloys or cobalt chromate, asexamples. Alternatively, the articulating socket 102 can be polishedmetal or plastic and not utilize a separate lining 112 (see front view600 of FIG. 6).

The articulating socket 102 may include a fitting 502 for interactionwith a stem component 106 (see side view 500 of FIG. 5). The fitting 502may be male or female and may be separately attached or formed as aone-piece construction as part of the articulating socket 102. It may bedesirable in revision surgery to utilize a female fitting 502 on thearticulating socket 102. In such a procedure, once the existing ball isremoved from the existing stem component, the female fitting 502 may beadapted to the male end of the stem, without removing it from thepatient's bone. Examples of fittings 502 may be trunnions, such as morsetaper trunnions. The fitting 502 may be centered on the distal or apexend of the articulating socket 102 or off set. The fitting 502 may beoff set from the centerline of the socket 102 about 5 to about 20degrees, about 10 to about 15 degrees or about 8 to about 12 degrees toallow for various configurations and positioning within the body.

The articulating socket 102 front surface (see view 400 of FIG. 4) maybe planar or curved, for example. The front surface may be curved so asto lessen the possibility of unwanted interactions with other componentsof the device. Additionally, the socket opening may be 180 degreesplanar when viewed from a side profile (see view 500 of FIG. 5) oralternatively, some angle less than 180 degrees. The articulating socket102 opening may be about 150 to about 180 degrees, about 160 to about170 degrees or about 165 to about 175 degrees, for example.

The ball 114 is supported in a substantially center position within thefixed socket 104 (see front view 300 of FIG. 3 and perspective view 700of FIG. 7). The center position may include attachment at the deepestportion of the socket 104, but also centered in height between the baseand opening of the socket 104. The ball 114 can be supported by a post118, such as a threaded post 802 (see view 800 of FIG. 8). The ball 114can be supported by a post 118 with a flared base 116 or pedestal thatresists or prevents substantial cantilever forces (see view 900 of FIG.9). The ball 114 may be one-piece construction with the post 118 andoptional base 116, for example. The post 118 may be threaded 802 withouta base 116 or with a flared base 116, such as shown in view 1000 of FIG.10. The post 118 may be of one-piece construction with the base 116, forexample.

The ball 114 may be contacted and supported by the fixed socket 104through an insertion tool fitting 1102 (and optionally 202 of FIG. 2),such as a screw hole (see cross sectional view 1100 of FIG. 11). Theinsertion tool fitting screw hole 1102 may not extend through the entirefixed socket wall, for example. A physician may utilize the screw holewhen inserting the original socket and in subsequent revision surgery asdescribed herein, can use the existing insertion tool fitting hole tosecure a new ball 114, via a post 118 or one-piece ball and postconstruction. The base 116 may match the curvature of the fixed socket104 and be secured using locking tabs or other mechanical fasteningmechanism or an adhesive, for example. Screw holes 206 (see FIG. 2) areoften available in fixed socket construction for securing the socket 104to bone, if needed. The base 116 may abut or partially cover these holes206 and be secured by deforming soft metal tabs positioned in the screwholes 206, sufficient to disallow unintentional unscrewing of the post118 or base 116 from the socket 104. The base 116 may be optionallysecured using a torque wrench (if threaded and in contact with a screwhole, for example), manually screwed, secured by soft or deformable tabsor adhered with adhesive or cement, as examples. The size of the base116 and surface area of the base may be as large as possible to increasesupport, but without being so large as to inhibit any desiredarticulation of the articulation socket 102 within the fixed socket 104.The base 116 may function as a stop for screw threading as well.

The fixed socket 104 may be substantially hemispheric and constructed ofa durable material, suitable for invasive medical insertion, such astitanium, metal alloys or cobalt chromate.

Similarly to the articulating socket 102, the fixed socket 104 frontsurface (see view 300 of FIG. 3) may be planar or curved, for example.The front surface may be curved so as to lessen the possibility ofunwanted interactions or impingements with other components of thedevice. Additionally, the socket opening may be 180 degrees planar whenviewed from a side profile or alternatively, some angle less than 180degrees. The fixed socket 104 opening may be about 150 to about 180degrees, about 160 to about 170 degrees or about 165 to about 175degrees, for example.

Referring to FIG. 12, a cross-sectional view 1200 of a reverse jointreplacement device is shown, according to some embodiments. Thearticulating socket 102 with optional lining 112 articulates with ball114. If a dislocation begins, the outer surface of 102 will then comeinto contact with inner surface 120 of fixed socket 104, thus preventingthe dislocation and supporting the force. An optional lining may bepositioned around the periphery of the inner surface 120 of the fixedsocket, such that when the outer surface of articulating socket 102(which may be polished) contacts the fixed socket 104, stablearticulation surfaces are utilized.

Referring to FIG. 13, a block flow diagram 1300 of a method of using ajoint replacement device is shown, according to some embodiments. Anarticulating socket is contacted 1302 with a stem component. Thearticulating socket is then contacted 1304 with a ball supported by afixed socket. In a revision surgery, an articulating socket may replacean existing ball on a stem component, such as a femoral stem component.A ball may be positioned in the fixed socket. Once again, if in arevision surgery, a ball may be attached to an existing fixed socketwithout removing it. The stem component may include a male or femalefitting and the articulating socket may be matched or adapted tointeract with a new or existing stem component.

In a primary surgery, there are more options for utilizing one-piececonstruction. The fixed socket and ball (with post and optional base)may be made of one-piece construction and inserted as a single unit.Similarly, the articulating socket may be formed of one-piececonstruction with the stem component. The stem component andarticulating socket may then be inserted as a single unit. The ball maybe of a differing material than base or stem to maximize thearticulation between ball and articulation socket.

Referring to FIG. 14, a block flow diagram 1400 of a method of making ajoint replacement device is shown, according to some embodiments. Afixed socket is formed 1402, including an inner surface and outersurface. A ball is formed 1404, supported by the inner surface of thefixed socket. The ball may be one-piece construction with the fixedsocket, for example. Alternatively, it can be formed separately andattached to the fixed socket. An articulating socket is formed 1406 anda stem component is formed 1408. The articulating socket may be ofone-piece construction with the stem component for example.Alternatively, the articulating socket may be formed separately andattached to the stem component.

The Abstract is provided to comply with 37 C.F.R. §1.72(b), to allow thereader to quickly ascertain the nature of the technical disclosure. Itis submitted with the understanding that it will not be used tointerpret or limit the scope or meaning of the claims.

What is claimed is:
 1. A reverse joint replacement device, the devicecomprising: a fixed socket having an outer surface attachable to a jointsocket, and a concave inner surface; a ball assembly having a ball, theball assembly being removably attached to the fixed socket concave innersurface; an articulating socket having a concave inner surface forarticulating with the ball, and an outer surface; and a stem component,connected to the outer surface of the articulating socket.
 2. The deviceof claim 1, wherein the ball assembly further comprises a post, and theball assembly removably attaches to the fixed socket concave innersurface via the post.
 3. The device of claim 2, wherein the ball andpost of the ball assembly are a one-piece construction.
 4. The device ofclaim 1, wherein the outer surface of the articulating socket canarticulate with the inner surface of the fixed socket.
 5. The device ofclaim 1 wherein the stem component and articulating socket are aone-piece construction.
 6. The device of claim 1, wherein the stemcomponent is removably connected to the outer surface of thearticulating socket.
 7. The device of claim 1 wherein the articulatingsocket further comprises a liner.
 8. The device of claim 1, wherein thestem component is attached to the articulating socket outer surface offset from the centerline of the articulating socket by about 0 degrees toabout 20 degrees.
 9. The device of claim 1, wherein the joint socket cancomprise one of an acetabulum or a glenoid fossa.
 10. The device ofclaim 1, wherein one or more of the ball assembly, the articulatingsocket, and the stem component can be removed or replaced in a revisionsurgery without detaching or replacing the fixed socket from the jointsocket.
 11. A reverse joint replacement socket device, the devicecomprising: a fixed socket having an outer surface attachable to a jointsocket, and a concave inner surface; a ball assembly having a ball, theball assembly being removably attached to the fixed socket concave innersurface.
 12. The device of claim 11, wherein the ball assembly furthercomprises a post, and the ball assembly removably attaches to the fixedsocket concave inner surface via the post.
 13. The device of claim 12,wherein the post is removably attached to the ball.
 14. The device ofclaim 12, wherein the post further comprises a base for resistingcantilever forces.
 15. The device of claim 12, wherein the ball and postof the ball assembly are a one-piece construction.
 16. The device ofclaim 11, wherein the ball assembly attaches to the fixed socket via ahole in the fixed socket inner surface which does not extend through theentire fixed socket.
 17. The device of 11, wherein the fixed socketcomprises an opening of about 150 degrees to about 180 degrees.
 18. Thedevice of claim 11, wherein the device is attachable to a joint socketvia the fixed socket, and the ball assembly can be replaced or removedfrom the fixed socket during a revision surgery without detaching thefixed socket from the joint socket.